This application claims the priority of German application 198 41 750.0, filed in Germany on Sep. 11, 1998.
The invention relates to a seat belt system for a motor vehicle, particularly for a two-wheeler. Preferred embodiments of the invention relate to a seat belt system for a two wheel motor vehicle for fixing a person on a vehicle seat, having two mutually independent seat belt straps which can be fastened by means of one belt buckle tongue respectively on one vehicle-fixed belt buckle respectively, in which case, by operating one unlatching device respectively on the pertaining belt buckle, one belt buckle tongue respectively can be released from this belt buckle and at least one additional operating device, which interacts with the unlatching devices of both belt buckles, is provided at an easily accessible point on the motor vehicle for releasing both belt buckle tongues from the respective pertaining belt buckle, the unlatching devices of both belt buckles being connected by way of at least one cable pull with the additional operating device.
German Patent Document DE 33 41 568 A1 describes a seat belt buckle with an automatic unlatching mechanism. In addition to its manual unlatching mechanism mounted directly on the buckle body, this seat belt buckle has an automatic unlatching mechanism, in the case of which the manual unlatching system can be triggered by way of a Bowden cable by means of another opening mechanism of a mechanical or electromechanical construction. This additional opening mechanism can also trigger several belt buckles in a remote-controlled manner.
Furthermore, it is known, particularly in the case of a two-wheeler, to use a seat belt system for fastening a person on a vehicle seat, which seat belt system has two mutually independent seat belt straps which can be fixed by means of one belt buckle tongue respectively on one belt buckle respectively which is fixed to the vehicle. By operating one unlatching mechanism respectively on the pertaining belt buckle, one belt buckle tongue respectively can be detached from the belt buckle and at least one additional operating device interacting with the unlatching mechanisms of both belt buckles is provided at an easily accessible point on the motor vehicle for detaching both belt buckle tongues from the respective pertaining belt buckle. The unlatching mechanisms of both belt buckles are connected by way of at least one cable pull with the additional operating device.
However, when the belt buckles are operated by way of an additional operating device by means of cable pulls, under certain circumstances, as a result of not compensating tolerances, only one belt buckle may release the belt buckle tongue. However, its cable pull will then block the operating lever such that the second belt buckle can be released only by means of its unlatching device directly on the belt buckle.
It is therefore an object of the invention to further develop a seat belt system of the above-mentioned time for a motor vehicle such that, as the result of an additional operating device, in each case, both belt buckle tongues of both belt buckles can be released.
According to the invention, this object is achieved by providing a system of the above-noted type wherein the additional operating device comprises a device for the length and/or force compensation operable to trigger the cable pull connection such that when the additional operating device is operated, both belt buckles are released, irrespective of whether releasing travels and/or releasing forces of different amounts must in each case be applied for the unlatching devices.
Further advantageous features of preferred embodiments of the invention are described herein and in the claims.
According to the invention, the additional operating device comprises a device for the length compensation and/or force compensation by means of which the cable pull connection is controlled such that, when the additional operating device is operated, both belt buckles are released, irrespective of whether differently long release paths and/or release forces must in each case be applied for the unlatching devices. Such a device for the length compensation and/or force compensation between two cable pulls, or both ends of one cable pull, advantageously has the result that the available force and/or the available path for releasing both belt buckles can be automatically distributed according to the respective force requirement and/or path requirement of the individual unlatching devices of the belt buckles onto these belt buckles. Thus, if a belt buckle has already been unlatched, the cable pull does not, as a result, block the additional operating device, but a length compensation and/or force compensation to the other cable pull takes place until the belt buckle controlled by this cable pull also releases the belt buckle tongue.
In the case of advantageous embodiments of the invention, the additional operating device comprises an operating lever, as a result of whose deflection a cable pull is moved, of which one end respectively is connected with an unlatching mechanism and which, as a device for the length compensation and/or force compensation, is guided in the additional operating device by way of a roller rotatably disposed in a connection carriage, the connection carriage transmitting the deflection movement of the operating lever to the roller.
The roller thus compensates length and/or force differences during the unlatching of both belt buckles in that the cable pull placed around these belt buckles, as a result of a rolling-off movement, can use its effective length according to the requirement for one belt buckle as well as for the other belt buckle.
According to another advantageous feature of preferred embodiments of the invention, the additional operating device comprises an operating lever, by means of whose deflection two cable pulls are moved, one of which respectively leading from the additional operating device to an unlatching mechanism, and their two unlatching-device-side ends, as a device for the length and/or force compensation in the additional operating device are connected by way of a joint piece which is connected at least swivellably with the operating lever.
If two cable pulls are used for triggering the two belt buckles, these are advantageously mounted for the length compensation and/or force compensation on a hinge piece which, in turn, is swivellably connected with the operating lever. Thus a rocker-type lever system is created which in a simple manner provides each cable pull with the length and/or force which the cable pull requires for opening the belt buckle, even if the other cable pull is already blocked by the open belt buckle.
Certain preferred embodiments of the invention are characterized in that the additional operating device comprises a restoring spring, in which case the connection carriage or the hinge piece are deflected by the operating lever against the force of the restoring spring. Such a restoring spring advantageously has the result that, after the unlatching, the unlatching devices of the belt buckles are set back into their latching position because the additional operating device, also as a result of the restoring spring, is set back into a position which corresponds to that of the latched belt buckles.
In certain preferred embodiments of the invention, another device for the length and/or force compensation is installed between the operating lever and the unlatching devices of the belt buckles. This device consists of at least one element which is elastic with respect to tension, particularly a tension spring. This additional device for the length and/or force compensation has the advantage that the operability can be adjusted to be softer and force peaks are compensated.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.